Computational and Experimental Study on Comparing the Methods of Retrofitting the Steel Lattice Tower under the Effect of Wind Load

Document Type : Regular Paper

Authors

1 Assistant Professor, Department of Civil Engineering , Damghan Branch, Islamic Azad University, Damghan, Iran

2 Master's Student, Department of Civil Engineering, Shahrood Non-Profit University, Shahrood, Iran

3 Ph.D., Department of Electrical Engineering, Shahrood University of Technology, Shahrood, Iran

Abstract

One of the common structures in power transmission towers is the steel lattice towers with the bolted connection type, which can be vulnerable to wind loads due to their low weight and high height. Due to the change in the wind design codes and the placement of new devices on these towers, retrofitting is inevitable. In this research, firstly, the effect of wind load on the mentioned structure has been investigated, in calculating the wind force on the structure, the coefficient that is related to the geometry of the structure is the CP coefficient. Wind pressure coefficients (CP) were obtained using Ansys software based on the structure's computational fluid dynamics (CFD) method. Based on the CFD analysis, the maximum positive pressure coefficient (pressure) and the maximum negative pressure coefficient (suction) are obtained as +1 and -1.2, respectively. Using the computational analysis of the structure under the effect of wind, it was observed that under the effect of wind load, the factor of instability of the structure can be the buckling of the compressive members. Therefore, seven models were studied under buckling test. The M1 model served as the base model consisting of a single angle, while the M2 to M7 models represented reinforced variations of the original design. Experimental and numerical results revealed that adding an angled connection along a section of the primary member's length (M4 model) can increase the member's resistance by 38%.

Graphical Abstract

Computational and Experimental Study on Comparing the Methods of Retrofitting the Steel Lattice Tower under the Effect of Wind Load

Highlights

  • Finding wind pressure coefficients on steel lattice tower using wind tunnel modeling in Ansys software.
  • Obtaining the first failure mode of the steel lattice tower
  • Providing solutions for retrofitting the compression members of the steel lattice tower.

Keywords

Main Subjects


[1]     Baran E, Akis T, Sen G, Draisawi A. Experimental and numerical analysis of a bolted connection in steel transmission towers. J Constr Steel Res 2016;121. https://doi.org/10.1016/j.jcsr.2016.02.009.
[2]     Li F, Deng H zhou, Hu X yi. Design resistance of longitudinal gusset-tube K-joints with 1/4 annular plates in transmission towers. Thin-Walled Struct 2019;144. https://doi.org/10.1016/j.tws.2019.106271.
[3]     Liang G, Wang L, Liu Y, Geng N. Mechanical behavior of steel transmission tower legs reinforced with innovative clamp under eccentric compression. Eng Struct 2022;258. https://doi.org/10.1016/j.engstruct.2022.114101.
[4]     Balagopal R, Ramaswamy A, Palani GS, Prasad Rao N. Simplified bolted connection model for analysis of transmission line towers. Structures 2020;27. https://doi.org/10.1016/j.istruc.2020.08.029.
[5]     Tapia-Hernández E, Ibarra-González S, De-León-Escobedo D. Collapse mechanisms of power towers under wind loading. Struct Infrastruct Eng 2017;13. https://doi.org/10.1080/15732479.2016.1190765.
[6]     Zou Y, Lei X, Yan L, He X, Nie M, Xie W, et al. Full-scale measurements of wind structure and dynamic behaviour of a transmission tower during a typhoon. Struct Infrastruct Eng 2020;16. https://doi.org/10.1080/15732479.2019.1670679.
[7]     Huang MF, Lou W, Yang L, Sun B, Shen G, Tse KT. Experimental and computational simulation for wind effects on the Zhoushan transmission towers. Struct Infrastruct Eng 2012;8. https://doi.org/10.1080/15732479.2010.497540.
[8]     Sun L, Trovato M, Stojadinović B. In-situ retrofit strategy for transmission tower structure members using light-weight steel casings. Eng Struct 2020;206. https://doi.org/10.1016/j.engstruct.2020.110171.
[9]     Xie Q, Zhang J. Experimental study on failure modes and retrofitting method of latticed transmission tower. Eng Struct 2021;226. https://doi.org/10.1016/j.engstruct.2020.111365.
[10]   Moon BW, Park JH, Lee SK, Kim J, Kim T, Min KW. Performance evaluation of a transmission tower by substructure test. J Constr Steel Res 2009;65. https://doi.org/10.1016/j.jcsr.2008.04.003.
[11]    Jiang WQ, Wang ZQ, McClure G, Wang GL, Geng JD. Accurate modeling of joint effects in lattice transmission towers. Eng Struct 2011;33. https://doi.org/10.1016/j.engstruct.2011.02.022.
[12]   Ma L, Khazaali M, Bocchini P. Component-based fragility analysis of transmission towers subjected to hurricane wind load. Eng Struct 2021;242. https://doi.org/10.1016/j.engstruct.2021.112586.
[13]   Ma R, Yu L, Zhang H, Tan L, Kueh ABH, Feng J, et al. Experimental and numerical appraisal of steel joints integrated with single- and double-angles for transmission line towers. Thin-Walled Struct 2021;164. https://doi.org/10.1016/j.tws.2021.107833.
[14]   An L, Wu J, Jiang W. Experimental and numerical study of the axial stiffness of bolted joints in steel lattice transmission tower legs. Eng Struct 2019;187. https://doi.org/10.1016/j.engstruct.2019.02.070.
[15]   Gan Y de, Deng H zhou, Li C. Simplified joint-slippage model of bolted joint in lattice transmission tower. Structures 2021;32. https://doi.org/10.1016/j.istruc.2021.03.022.
[16]   Karimian Sichani M, Keramati A, Behzadinia F. Modification of the euler load for the stiffened compressive members and determination of the optimal stiffening for the maximum buckling load. J Rehabil Civ Eng 2020;8. https://doi.org/10.22075/JRCE.2020.19819.1385.
[17]   Vettoretto G, Li Z, Affolter C. Evaluation of the Ultimate Collapse Load of a High-Voltage Transmission Tower under Excessive Wind Loads. Buildings 2023;13. https://doi.org/10.3390/buildings13020513.
[18]   Mianroodi M. Experimental and numerical CPFEM-based determination of FLD using biaxial and Nakajima tests: industrial application to deep drawing simulation for FCC and BCC metals 2021.
[19]   Bazmara M, Mianroodi M, Silani M. Application of physics-informed neural networks for nonlinear buckling analysis of beams. Acta Mech Sin 2023;39:422438.
[20]     Mianroodi M, Touchal S, Altmeyer G. Comparison of Forming Limit Diagrams for FCC and BCC materials using Taylor and Marciniak-Kuczynski models. Int. Conf. Sci. Eng. Technol. ICSET 2019, vol. 7, 2019.